Kinetics of dyeing natural protein fibers with silver nanoparticles

The kinetics of dyeing silk and wool fibers with silver nanoparticles was investigated by ultraviolet-visible (UV-Vis) absorption spectroscopy at different temperatures. Silver nanoprisms (AgNPrs) acting as novel dyestuffs endowed fibers with blue color because of their localized surface plasmon resonance. Color characteristics of dyed fibers were measured and analyzed. The dyeing rate of fibers with AgNPrs increased with an increase in temperature. Compared with wool, silk exhibited faster dyeing rate with AgNPrs. The pseudo-first-order model described suitably the initial stage of the dyeing process of silk and wool based on AgNPrs. Whereas, the entire dyeing process except for the beginning stage followed the pseudo-second-order model appropriately. Traditional dye (acid blue 199) was used for comparison with AgNPrs. The pseudo-second-order model fitted the entire dyeing process with acid blue 199 better. Activation energy for silk dyeing with AgNPrs was the lowest among the examined dyeing systems, demonstrating that AgNPrs combined most easily with silk fibers. Thermodynamic activation parameters for the adsorption of AgNPrs and acid blue 199 onto fibers were obtained to investigate the involved dyeing process of silk and wool.